Difference between revisions of Diopters
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Dlskidmore (talk | contribs) (Expanded definition) |
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| − | + | Diopters is a measure of the power of a [[lens]] (or mirror). It is equal to 1/[[focal length]] in meters. In EM we refer to the [[cm measurement]] to calculate diopters needed to correct [[refraction]] of the eye. | |
| − | + | A lens with a negative diopter sign compensates for [[nearsightedness]] while a lens with a positive diopter sign compensates for [[farsightedness]] | |
| − | + | Approximate categorizations of myopia by lens power: | |
| − | + | 0.00 - -0.75 - Probably don't need glasses | |
| − | 10.00+ - Very high myopia. Field of view significantly reduced. | + | -1.00 - -2.00 - Mild myopia, no [[differentials]] needed |
| + | |||
| + | -2.00 - -5.00 - Moderate myopia, glasses always needed | ||
| + | |||
| + | -5.00 - -10.00 - High myopia | ||
| + | |||
| + | -10.00+ - Very high myopia. Field of view significantly reduced. | ||
Revision as of 19:22, 18 May 2020
Diopters is a measure of the power of a lens (or mirror). It is equal to 1/focal length in meters. In EM we refer to the cm measurement to calculate diopters needed to correct refraction of the eye.
A lens with a negative diopter sign compensates for nearsightedness while a lens with a positive diopter sign compensates for farsightedness
Approximate categorizations of myopia by lens power:
0.00 - -0.75 - Probably don't need glasses
-1.00 - -2.00 - Mild myopia, no differentials needed
-2.00 - -5.00 - Moderate myopia, glasses always needed
-5.00 - -10.00 - High myopia
-10.00+ - Very high myopia. Field of view significantly reduced.
